Ammunition



Sept. 23, 1952 P. P. ALEXANDER AMMUNITION Filed June 14, 194918212382303 Eda? M LEE 5302 2203;

Patented Sept. 23, 1952 AMMUNITION Peter P. Alexander, Beverly, Mass.,assignor to Metal Hydrides Incorporated, Beverly,.Mass., a company-ofMassachusetts I Application' June 14, 1949, Serial No. 99,097

This invention relates to bullets or projectiles for ammunition-toruseinrifles, guns, etc. Such bullets or projectiles usuallyare fitted in acartridge case containing an-explosiv'e chargewhich, when -detona'ted,propels the projectile from the gurrat a predetermined velocity. Thecartridge case contains means for detonating the explosive charge, whichcommonly is a detonator cap fitted in the base of the cartridge case,adapted to be detonated by the impact of the gun hammer. 'In-some cases,a ring of a soft metal, such as copper, is fitted in an annular groovein the projectile for a purpose well known to those skilledinordnance.

Prior to the present invention it had been known that spar-ksare-produced when a hard metal, suchas iron, was subjected to theviolent abrasive action of an abrasive Wheel rotating at high speed.When brittle iron is subjected to impact sufficient to break'itintosmall pieces no sparks are produced. The action of an abrasive wheelupon iron generates considerable heat which raises the'temperature ofthesmall particles removed sufficiently high to cause them to glow.

It also was known that certain alloys, such as alloys containing about;70 per cent cerium and 30 per cent iron; produce sparks when subjectedto mild abrasion, such as by rotating a small knurled wheel a partialrevolution while contactingthe alloy under very slight pressure. Themild abrasion does not generate any substantial amount of heat. Theproduction of sparks by these alloys has been explained by those skilledin the art as being caused by the removal of a multiplicity of smallparticles which immediately become ignited in air. Such alloys arereferred to as pyrophoric alloys. They contain a large percentage of avery soft metal, namely, cerium.

Another pyrophoric alloy i described in the copending application ofRobert J. Anicetti, Serial No. 746,329, filed May 6, 1947, now PatentNo. 2,490,570. This pyrophoric alloy consists essentially of zirconiumand lead in the proportions of 20 to 75 per cent of lead and 25 to 80per cent of zirconium by weight. Like the cerium-iron alloy, thezirconium-lead alloy produces sparks when subjected to mild abrasion byrotating a small knurled wheel a partial revolution while contacting thealloy under very slight pressure. It too contains a very soft metalcomponent, namely, lead.

In spite of the similarity in appearance and the above mentionedproperties of the ceriumiron alloy and the lead-zirconium alloy, they .1Claim.. (01.102-38.)

differ radically in at leastone property. Thus, I have made thesurprising discovery that-when a piece-of the lead-zirconium alloy issubjected to a sudden heavy impact, instead of being broken intofragments, it is crushed to a fine powder and the whole mass set afire.The pres entinvention is based upon this discovery --and the conceptionof utilizing this peculiarproperty of the lead-zirconium alloy byembodying the alloy in projectiles for ammunition. I have dis coveredthat alloys which are essentiallyliead and zirconium in the proportionsof 10 to per cent of lead and 30 to per cent of zir conium by weightpossess this property and-are suitable for use in the practice of theinvention. It the projectile is composed wholly of this alloy, I preferto employ an alloy containing between about -50. to 60 per cent byweightof leadbe cause ofits better ballistic characteristics-.wIt wassurprising to discover that" an alloy of fi-zir conium and lead,containing afhigh-percerrtage of lead possesses this peculiar propertysince "it was well known that bullets madeof lead o r' 1ea cl alloystheretofore tended to flatten upon striking atarget: f The alloy maycontain substantial amountsof diluting metals such as titanium,manganese, tin, antimony,'etc., without detrimentally affect ing itsbasic characteristics. The combined amounts of lead and zirconium shouldnot be less than about 60 per cent by weight of the alloy. I prefer,however, that the alloy contain not more than minor amounts of diluents.

In accordance with the present invention, ammunition for rifles, guns,etc., is provided in which the bullets or projectile is formed eitherwholly or in part of the pyrophoric alloy of lead and zirconium. Inaccordance with one aspect of the invention, a small piece of thepyrophoric alloy may be secured in the tip of the bullet such as thehole in the open point bullet, to provide ammunition particularlysuitable for target practice either in daylight or in darkness. Whensuch a bullet strikes a hard target, the alloy is set afire and informsthe marksman, either military or civilian, as to the location of thehit. If desired a small amount of a smoke producing compound, such asblack powder, magnesium metal, etc., may be placed in the bullet so thatit is ignited by the pyrophoric alloy when the bullet strikes thetarget, thus supplementing the flame produced by the pyrophoric alloyand producing smoke which can be seen by the marksman. If desired, anyknown incendiary composition may be placed in the bullet 0r projectileso that it may be crushed under oil or in a neutral protectiveatmosphere, such as argon, to form coarse particles which may be mixedwith a binder such as glyptol, and shaped to desired form by molding,extruding, etc. While a fine powder ofv about 325 mesh still iscrystalline; it cannot-bet crushed further and is not desirable for usein the practice of the invention. The. particle. size should be suchthat the particle will split or crush at the predetermined velocity forwhich. the at ticle of ammunition is designed to propel the projectileagainst. the target. Where: the predetermined velocity is about 10.00feet per. second,

7 the'particle size. should be of. the order of 100 mesh.

Theinvention, therefore. in its" broad aspect contemplates ammunitioninwhichat. least a portion of. the bullet or projectile is formed of. apyrophoric. alloy. In one embodiment, a piece of pyrophoric alloy issecuredin a. hole in the tip 01 the bullet so as to project forwardtherefrom. The act-ionof thepyrophoric alloy may be supplemented by anadditional smoke and. flame producing. compound: adapted. to be.ignited. by the sparks. or flameiproduced by the. pyrophoric alloy whenthe bullet. impacts a hard. target. When theentire bulletor. projectileis a pyrophoric alloy oi zirconium-lead, the lead component should. berelatively high sothat the density of the alloy is notv less than.about; 6.5. because of. its better ballistic characteristics. 1

' The invention isillustrated further in the accompanying drawing, inwhich;

EigrLi's anelevational view of. apieceoflammunifihnsembodying. theinvention; and- Fig.2 is an elevational view, partly in section, 01 an.open point bullet embodyingv the invention.

Thev embodiment illustrated in Fig.. 1. comprises 7 a: cartridge case-In of brass. intothe open end. or

v 4 which a, bullet or projectile II is fitted. in the usual manner. Theprojectile I l is formed of an alloy which is essentially zirconium andlead. A ring 12 of copper may be fitted into an annular groove formed inthe body of the projectile near its rear end.

Fig. 2 illustrates a piece of ammunition for small arms. having anoperrpoint expanding bullet l3 fitted in the open end ofa,brasscartridge case M. The bullet I3 may be formed of lead or othermetal commonly employed and is provided with a hole. IS in its tip. Asillustrated, a smoke producing compound l6, such as black powder, isplaced in the bottom of the hole I 5 and a piece H of the" pyrophoric.alloy is fitted in the hole so as to project forwardly a short distancefrom the tip of. the. bullet.

I This application is a continuation-in-part of mycopending application,Serial No. 18,642, filed April 2, 1948, now abandoned.

I.claim:

In an. article of. ammunition having; a cartridgecase and. a projectilefitted. therein. and in which a portionof the. projectile isignitible.uponimpact with a target, the improvement wherein. said ignitible.portion is av pyrophoric. alloy consisting essentially of. zirconium.and betweenabout to per cent of lead by weight and. projects forwardlyfrom. the tip of the projectile and is thereby adapted to come indirectcontact withfa hard target whereby the force of impact therewithvcauses. said. alloy to be crushed to a finely divided condition andthusv be set afirel PETER P. '1

REFERENCES CITED The: following references are of record in the file ofthis patent:

UNITED sTnrrEs. PATENTS I Great. Britain-1.1--. une 1551933

